CN110387485B - Component design method of metastable beta titanium alloy - Google Patents

Component design method of metastable beta titanium alloy Download PDF

Info

Publication number
CN110387485B
CN110387485B CN201910643057.6A CN201910643057A CN110387485B CN 110387485 B CN110387485 B CN 110387485B CN 201910643057 A CN201910643057 A CN 201910643057A CN 110387485 B CN110387485 B CN 110387485B
Authority
CN
China
Prior art keywords
alloy
energy
work function
elements
yield strength
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910643057.6A
Other languages
Chinese (zh)
Other versions
CN110387485A (en
Inventor
寇宏超
王晓丹
王毅
邹程雄
唐斌
樊江昆
赖敏杰
李金山
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Northwestern Polytechnical University
Original Assignee
Northwestern Polytechnical University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Northwestern Polytechnical University filed Critical Northwestern Polytechnical University
Priority to CN201910643057.6A priority Critical patent/CN110387485B/en
Publication of CN110387485A publication Critical patent/CN110387485A/en
Application granted granted Critical
Publication of CN110387485B publication Critical patent/CN110387485B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C14/00—Alloys based on titanium
    • G—PHYSICS
    • G16—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR SPECIFIC APPLICATION FIELDS
    • G16C—COMPUTATIONAL CHEMISTRY; CHEMOINFORMATICS; COMPUTATIONAL MATERIALS SCIENCE
    • G16C20/00—Chemoinformatics, i.e. ICT specially adapted for the handling of physicochemical or structural data of chemical particles, elements, compounds or mixtures
    • G16C20/10—Analysis or design of chemical reactions, syntheses or processes

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • Bioinformatics & Computational Biology (AREA)
  • Computing Systems (AREA)
  • Theoretical Computer Science (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

A component design method of a metastable beta titanium alloy takes first principle calculation as a core, and combines Mo equivalent, d electron theory and yield strength check to carry out component design of the metastable beta titanium alloy. The first principle is to design the alloy from atomic layer to obtain macroscopically high-performance material, but the span is too large from atomic scale to macroscopic scale, which results in larger difference between simulation or calculation results and actual conditions. Therefore, the invention also adopts a method for verifying Mo equivalent, d electron theory and yield strength. The composition checking based on Mo equivalent and d electron theory is mainly based on phase stability, and the dimension plays a role in starting from the atomic dimension of the first principle to the macroscopic dimension of the yield strength test. The effective scale spanning realizes effective spanning from atomic scale to macroscopic size, improves the accuracy of the design method, and simultaneously realizes the reduction of the research and development cost of novel materials and the improvement of the research and development efficiency.

Description

Component design method of metastable beta titanium alloy
Technical Field
The invention belongs to the technical field of titanium alloy, and relates to a component design method of metastable beta titanium alloy.
Background
The metastable beta-type titanium alloy is an alloy which can completely retain beta phase without martensitic transformation after being quenched to room temperature, and can obtain higher tensile strength after heat treatment. Most of the high-strength titanium alloys widely applied at home and abroad at present are metastable beta titanium alloys, such as Ti1023, VT22 and derivative alloys Ti-5553 and Ti-55531 which are applied to key force bearing parts such as aircraft landing gears such as EL-76, Boeing 787, EL-96-300 and airbus A350, and connecting devices of wings and hangers, and the weight reduction is more than 30%. Therefore, the metastable beta titanium alloy is one of the key development directions of the high-strength titanium alloy.
At present, the alloy design methods applied to the titanium alloy field mainly include a trial and error method, a Mo equivalent design method, a d-electron theory design method, an alloy design method based on a fuzzy logic neural network technology, an expert database and the like. Trial and error methods rely on a large number of experimentsAnd a large amount of screening can be carried out to obtain a material with better performance, and the method has contingency and blindness. For a multi-component titanium alloy system, Mo equivalent can be used as the basis of the addition of alloy elements in the design process of titanium alloy, but the control of Mo equivalent is difficult to determine the alloy elements and the proportion, and meanwhile, the phenomenon that different alloys with the same Mo equivalent have different mechanical properties cannot be explained. Alloy design based on d-electron theory
Figure GDA0002761324800000011
And
Figure GDA0002761324800000012
value controlling the phase stability and properties of the alloy, the structural type of the unknown alloy can be determined, but
Figure GDA0002761324800000013
And
Figure GDA0002761324800000014
the variation of the value with concentration is a simple linear relationship, and cannot explain the experimental fact that the crystal structure parameters and properties of the alloy are complexly changed with the concentrations of the constituent elements, and cannot predict the variation of the alloy properties caused by the variation of the atomic arrangement, so that the method has a limited role in the design process of the titanium alloy. The fuzzy logic neural network technology and the expert database simulation have high precision, but have unclear physical meaning and are difficult to be deep into the microscopic nature.
In the invention creation with publication number CN108446478A, the university of central and south proposed a design method of a multi-component high-strength titanium alloy. The method mainly comprises the steps of preparing a diffusion section, and measuring the microstructure and the microhardness corresponding to alloys with different components in the diffusion section, so as to establish a database of the corresponding relation of the components, the structure and the hardness of the titanium alloy. Compared with other alloy design methods, the method has higher pertinence and higher practical value. However, the method completely depends on experimental means, the cost is high, and the period from preparation to diffusion welding to component structure performance testing is long.
In the invention creation with the publication number of CN101763450A, Liaoning industry university provides a method for quantitative design of titanium alloy components. The method starts from the actual phase change of the titanium alloy, and establishes a calculation formula of the strength increment and the elongation reduction of the titanium alloy under different heat treatment conditions on an electronic structure level, so as to design the alloy components meeting the design requirements. The design method realizes high efficiency, high speed and low cost, but the method completely depends on a calculation and prediction means, and directly spans from an electronic structure level to a macroscopic performance level of the material, so that the span of the design method is too large, the physical significance of the design method is not clear, and the calculation result is greatly different from the actual situation.
Disclosure of Invention
In order to solve the problems of high design cost, long period, large difference between simulation calculation results and actual conditions and the like of the titanium alloy in the prior art, the invention provides a component design method of a metastable beta titanium alloy.
The specific process of the invention is as follows:
step 1, establishing a Ti-Xi alloy system and calculating the lattice distortion energy delta E thereof by utilizing a first principle calculation methodLDiFormation enthalpy Δ HiAnd electron work function phiiAnd the influence of the addition of the alloy elements on the alpha phase stability and the electronic structure is contrastively analyzed, the alloy elements are selected, and a target research system is determined.
The specific calculation method is as follows:
i establishment of Ti-XiThe alloy system of (1):
adding any metal element in the periodic table of elements into pure titanium to establish Ti-XiWherein i is 1,2, … … n. Using aluminium as alloy element X1Adding to pure titanium to form Ti-X1The method is characterized in that the method comprises the following steps of,
II determining Ti-X1Lattice distortion energy Δ E of the alloy system of (1)LDFormation enthalpy Δ H and electron work function Φ:
calculating the lattice distortion energy Delta ELD1And enthalpy of formation Δ H1The specific calculation process is as follows:
establishing pure titanium super crystal cell model by using vesta software and adding alloy element X1Ti-X of1A super cell model, which is prepared by VASP software in a computer cluster1The volume of the super-cell model is scaled according to different proportions in sequence to obtain pure titanium super-cell models and Ti-X with different volumes respectively1Super cell model. The scaling ratios are 0.96, 0.98, 1.00, 1.02 and 1.04, respectively.
For the obtained pure titanium super crystal cell models with different volumes and Ti-X1The super cell model was calculated statically. Respectively obtaining pure titanium super-cell models and Ti-X with different volumes1The total internal energy Ev and the deformation volume V of the super cell model in the static state.
The obtained pure titanium super-cell models with different volumes and Ti-X1The total internal energy Ev and the deformation volume V of the super cell model are respectively brought into a four-parameter Birch-Murnaghan state equation to carry out the fitting of the equilibrium state property, and the equilibrium energy E of the pure titanium is obtained0(Ti) and Ti-X1Equilibrium energy E of the system0(Ti-X1)。
By the equilibrium energy E of the pure titanium obtained0(Ti) and Ti-X1Equilibrium energy E of the system0(Ti-X1) Determining the lattice distortion energy Δ E using equation (1)LD1：
ΔELD1＝E0(Ti-X1)-E0(Ti).....................................(1)
Build up alloy element X1The unit cell structure model of (1) is obtained by VASP software in a computer cluster for the alloy element X1The volume of the unit cell model is scaled according to different proportions in sequence to respectively obtain the alloy element X1Unit cell models at different volumes. The scaling ratios are 0.96, 0.98, 1.00, 1.02 and 1.04, respectively.
To alloy element X1Static calculation is carried out on the unit cell models under different volumes to respectively obtain the alloy element X1The total internal energy Ev and the deformation volume V of the cell model at different volumes in the static state.
The obtained alloy element X1Different bodyThe total internal energy Ev and the deformation volume V of the accumulated unit cell model in the static state are respectively brought into a four-parameter Birch-Murnaghan equation of state for fitting the property of the equilibrium state, and the alloy element X is obtained1Equilibrium energy E of0(X1)。
Ti-X obtained by the above1Equilibrium energy E of the system0(Ti-X1) And an alloying element X1Equilibrium energy E of0(X1) Determining the enthalpy of formation Δ H using equation (2)1：
Figure GDA0002761324800000031
Wherein the content of the first and second substances,
Figure GDA0002761324800000032
is Ti-X1Alloy element X in the system1Molar mass of (a).
Calculating Ti-X by using first-nature principle calculation method1Electron work function of the system phi1。
Ti-X1Electron work function of the system phi1The calculation formula of (2) is as follows:
Figure GDA0002761324800000033
where α is an intrinsic constant determined by the properties of the material itself, Ti-X1α of the alloy is 1; r issIs the electron volume effective radius; eFIs a fermi energy.
Thus, Ti-X was determined1Lattice distortion energy of the system Δ ELD1Formation enthalpy Δ H1And electron work function phi1。
III calculation of Ti-XiLattice distortion energy Δ E of the remaining elements in the systemLDiFormation enthalpy Δ HiAnd electron work function phii：
The Ti-XiThe rest elements in the system are metal elements except aluminum in the periodic table of elements.
Repeating said step II to respectively obtain said Ti-XiThe rest elements in the system are added into the pure titanium one by one to form n-1 Ti-X elements in turniSystem i 2,3, … … n and calculating each Ti-X in turn according to the calculation method described in said iiiLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phiiUntil said n-1 Ti-X are obtainediLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phii。
Obtaining Ti-X consisting of all metal elements in the periodic table of the elements through the II and the IIIiLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phii。
Ti-X composed of all metal elements in the periodic table obtained by comparisoniLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phiiAnd selecting alloy elements to form a target research system.
The criteria for selecting the alloy elements are as follows:
i, the lattice distortion caused by the addition of the element is smaller;
ⅱTi-Xithe absolute value of the formation enthalpy of the system is large;
ⅲTi-Xithe electron work function of the system is large.
Step 2, calculating the yield strength sigma of the target research system0.2：
Calculating yield strength sigma of target research system based on alloy strengthening model0.2。
The alloy strengthening model is as follows:
σ0.2＝K1Φ6+C...................................................(4)
k in alloy strengthening model1And C is a constant term, where K1＝-1.0653，C＝5076.19251。
The main role of the alloy strengthening model is the electron work function phi of a target research system; the calculation formula of the electron work function phi of the target research system is as follows:
Φ＝∑zkφk...................................................(5)
where Φ is the electron work function of the target research system; z is a radical ofkIs the molar mass of the k element, phikIs the electron work function of the Ti-K system.
Obtaining the yield strength sigma in a target research system through the alloy strengthening model0.2Electronic work function phi and yield strength sigma of alloy larger than 1200MPa0.2。
And 3, checking the components based on the Mo equivalent and the d electronic theory design criterion:
the designed alloy meets the requirement that the Mo equivalent is 9-11, and the Mo equivalent is determined by a Mo equivalent calculation formula.
Designed metastable beta titanium alloy
Figure GDA0002761324800000041
And
Figure GDA0002761324800000042
the temperature should be controlled within 2.30-2.42 and 2.75-2.82 respectively.
Of target research systems
Figure GDA0002761324800000043
Value sum
Figure GDA0002761324800000044
The calculation of the values is as follows:
Figure GDA0002761324800000045
Figure GDA0002761324800000046
in the formula: a iskIs the atomic percentage of the k element, (Md)kAnd (Bo)kMd and Bo values of k elements, respectively(ii) a The Md value is the d orbital energy of any alloy element, is related to charge transfer, and shows the electronegativity characteristic of the alloy element;
Figure GDA0002761324800000047
is the average value of the Md values of all the alloy elements in a target research system; the Bo value is the overlap of electron clouds between atoms and is a measure of the strength of covalent bonds between atoms;
Figure GDA0002761324800000048
is the average value of the values of each alloying element Bo in the target research system.
The calculation results show that the yield strength sigma in step 20.2The Mo equivalent of the alloy more than 1200MPa is 9-11,
Figure GDA0002761324800000049
the values are all between 2.30 and 2.42,
Figure GDA00027613248000000410
the values are all between 2.75 and 2.82, and the design requirements are met.
Step 4, smelting the cast ingot, carrying out mechanical treatment, testing the yield strength of the cast ingot, and verifying the accuracy of design:
the method comprises the steps of proportioning according to specific chemical components of the alloy meeting yield strength requirements, preparing an ingot with the weight of more than 20 kilograms by using a vacuum consumable melting furnace according to a conventional method, carrying out solid solution aging heat treatment after cogging and forging, testing the yield strength of the alloy, verifying the correctness of a design result, and finishing the design of the metastable beta titanium alloy.
The invention relates to a component design method of a metastable beta titanium alloy, which comprises the following specific steps: calculating and comparatively analyzing the influence of the addition of different alloy elements on the alpha phase stability and the electronic structure by using a first principle calculation method, selecting the alloy elements and determining a target research system; calculating the yield strength of a target research system based on a strengthening model, and screening alloy components meeting the yield strength requirement; performing component checking on alloy components meeting the yield strength requirement based on Mo equivalent and d electronic theory design criteria, wherein Mo equivalent is used for ensuring that the alloy has higher strength, and d electronic theory is used for ensuring that the alloy belongs to metastable beta-type titanium alloy; the method comprises the steps of proportioning according to specific chemical components of the alloy meeting yield strength requirements, preparing an ingot with the weight of more than 20 kilograms by using a vacuum consumable melting furnace according to a conventional method, carrying out solid solution aging heat treatment after cogging and forging, testing the yield strength of the alloy, verifying the correctness of a design result, and finishing the design of the metastable beta titanium alloy.
The invention takes the first principle calculation as the core and combines Mo equivalent, d electron theory and yield strength check to carry out the component design of the metastable beta titanium alloy. The first principle is to design the alloy from atomic layer to obtain macroscopically high-performance material, but the span is too large from atomic scale to macroscopic scale, which results in larger difference between simulation or calculation results and actual conditions. Aiming at the problem, the invention adopts a first principle, and also adopts a method of Mo equivalent, d electron theory and yield strength check. The composition checking based on Mo equivalent and d electron theory is mainly based on phase stability, and the dimension plays a role in starting from the atomic dimension of the first principle to the macroscopic dimension of the yield strength test. The effective scale spanning realizes effective spanning from atomic scale to macroscopic size, and improves the accuracy of the design method.
The alloy design method provided by the invention realizes effective spanning from atomic scale to macroscopic size, can more accurately design the material of the metastable beta titanium alloy, has an error between the experimental value and the predicted value of the yield strength of the designed alloy smaller than 10%, is easy to realize, saves time-consuming tedious steps of cleaning and proportioning raw materials for obtaining repeated ideal alloy components, smelting and preparing the alloy, cutting and polishing, analyzing and testing consumables compared with the traditional research method, saves research costs of the raw materials, experimental equipment and the like, can save 2/3 time in comparison, is efficient and quick, and simultaneously realizes reduction of research and development costs and improvement of research and development efficiency of the metastable beta titanium alloy material.
Detailed Description
The invention relates to a component design method of metastable beta titanium alloy, which comprises the following steps: calculating the influence of the addition of alloy elements on the phase stability of the enhanced phase and the influence on the electronic structure of the enhanced phase by using a first principle calculation method, and determining a target research system by comparing the influence of different alloy elements on the phase stability of the enhanced phase and the influence on the electronic structure of the enhanced phase; calculating the yield strength of a target research system based on a strengthening model, and screening alloy components meeting the yield strength requirement; performing component checking on alloy components meeting the yield strength requirement based on Mo equivalent and d electronic theory design criteria, wherein Mo equivalent is used for ensuring that the alloy has higher strength, and d electronic theory is used for ensuring that the alloy belongs to metastable beta-type titanium alloy; preparing 20 kg of cast ingots of the alloy meeting the yield strength requirement by using a vacuum consumable melting furnace according to a conventional method, carrying out solid solution aging heat treatment after cogging and forging, testing the yield strength of the alloy to verify the correctness of a design result, and finishing the design of the metastable beta titanium alloy.
The embodiment comprises the following steps:
step 1, establishing a Ti-Xi alloy system and calculating the lattice distortion energy delta E thereof by utilizing a first principle calculation methodLDiFormation enthalpy Δ HiAnd electron work function phiiAnd the influence of the addition of the alloy elements on the alpha phase stability and the electronic structure is contrastively analyzed, the alloy elements are selected, and a target research system is determined.
The specific calculation method is as follows:
i establishment of Ti-XiThe alloy system of (1):
and calculating the influence of the addition of the alloy elements on the phase stability of the enhanced phase and the influence on the electronic structure of the enhanced phase by using a first principle calculation method.
The alloy elements are metal elements in the periodic table of elements.
And comparing the influence of different alloy elements on the phase stability of the enhanced phase with the influence on the electronic structure of the enhanced phase, and determining a target research system.
Adding any metal element in the periodic table of the elements into pure titanium to establish Ti-XiWherein i is 1,2, … … n.
In this example, aluminum was used as the alloying element X1Adding to pure titanium to form Ti-X1And (4) preparing the system.
II determining Ti-X1Lattice distortion energy Δ E of the alloy system of (1)LD1Formation enthalpy Δ H1And electron work function phi1：
Calculating the Ti-X by using a first principle calculation method1Lattice distortion energy of the system Δ ELD1And enthalpy of formation Δ H1(ii) a The lattice distortion energy Delta ELD1And enthalpy of formation Δ H1The size of (b) reflects the influence of the addition of the alloying elements on the stability of the reinforcing phase.
The lattice distortion is Ti-X1The crystal lattice of the system is distorted, thereby causing the potential energy to be increased, the mixed width of the system to be increased, the free energy to be increased, and the Ti-X is caused1The system stability is reduced. The degree of increase in free energy during lattice distortion is lattice distortion energy Δ ELD1. Lattice distortion energy Δ ELD1The larger the alloy system, the more unstable.
The enthalpy of formation Δ H1The alloy element added into the pure titanium is kept at room temperature and standard atmospheric pressure, and 1mol of pure substance thermal effect, namely enthalpy of generation is generated by utilizing the most stable simple substance of the alloy element. The larger the absolute value of enthalpy of formation, the larger the Ti-X1The larger the bond energy of the system, the lower the energy, and the more stable the system, so Ti-X1The larger the absolute value of the enthalpy of formation of the system, the more stable the system.
Ti-X1Lattice distortion energy of the system Δ ELD1And enthalpy of formation Δ H1The specific calculation process of (2) is as follows:
the reinforcing phase of the titanium alloy is alpha phase, so the model structure is HCP structure, the vesta software is used to build up pure titanium super crystal cell model and add alloy element X1Ti-X of1A super cell model, which is prepared by VASP software in a computer cluster1The volume of the super-cell model is scaled according to different proportions in sequence to obtain pure titanium super-cell models and Ti-X with different volumes respectively1Super cell model. What is needed isThe scaling ratios are 0.96, 0.98, 1.00, 1.02 and 1.04, respectively.
For the obtained pure titanium super crystal cell models with different volumes and Ti-X1The super cell model was calculated statically. Respectively obtaining pure titanium super-cell models and Ti-X with different volumes1The total internal energy Ev and the deformation volume V of the super cell model in the static state.
The obtained pure titanium super-cell models with different volumes and Ti-X1The total internal energy Ev and the deformation volume V of the super cell model are respectively brought into a four-parameter Birch-Murnaghan state equation to carry out the fitting of the equilibrium state property, and the equilibrium energy E of the pure titanium is obtained0(Ti) and Ti-X1Equilibrium energy E of the system0(Ti-X1)。
The specific expression of the four-parameter Birch-murnaghan state equation is as follows:
Figure GDA0002761324800000071
wherein Ev is the total internal energy under different scaling systems; v is the deformation volume under different scaling systems; e0Is the fitted equilibrium energy; v0Is the fitted equilibrium volume; b is0Is the bulk modulus, B0' is for phantom volume deviation in the pressure state.
By the equilibrium energy E of the pure titanium obtained0(Ti) and Ti-X1Equilibrium energy E of the system0(Ti-X1) Determining the lattice distortion energy Δ ELD1The expression is as follows:
ΔELD1＝E0(Ti-X1)-E0(Ti).....................................(1)
build up alloy element X1The unit cell structure model of (1) is obtained by VASP software in a computer cluster for the alloy element X1The volume of the unit cell model is scaled according to different proportions in sequence to respectively obtain the alloy element X1Unit cell models at different volumes. The scaling ratios are 0.96, 0.98, 1.00, 1.02 and 1.04, respectively.
To alloy element X1Static calculation is carried out on the unit cell models under different volumes to respectively obtain the alloy element X1The total internal energy Ev and the deformation volume V of the cell model at different volumes in the static state.
The obtained alloy element X1The total internal energy Ev and the deformation volume V of the unit cell model under different volumes are respectively brought into a four-parameter Birch-Murnaghan equation of state to carry out the fitting of the property of the equilibrium state, and the alloy element X is obtained1Equilibrium energy E of0(X1)。
Ti-X obtained by the above1Equilibrium energy E of the system0(Ti-X1) And an alloying element X1Equilibrium energy E of0(X1) Determining said enthalpy of formation Δ H1The expression is as follows:
Figure GDA0002761324800000081
wherein the content of the first and second substances,
Figure GDA0002761324800000082
is Ti-X1Alloy element X in the system1Molar mass of (a).
Next, Ti-X is calculated using a first principle calculation method1Electron work function of the system phi1。
The electron work function phi1Reflecting the interaction between atoms or the interaction between atomic nucleus and surrounding electrons, the addition of alloy elements in the system redistributes the electrons, which is helpful for increasing the work function phi of the electrons1The value is obtained.
In Chengxiong Z, Jinshan L, Yi W, et al, reforming the local magnetic strains and strain mechanics of Ti alloys [ J]The yield strength and electron work function φ of the alloy is disclosed in the comparative Materials Science,2018,152:169-1In a hexagonal relationship, Ti-X1Electron work function of the system phi1The larger the value, the higher the alloy yield strength.
Ti-X1Electronic work function of systemNumber phi1The calculation formula of (2) is as follows:
Figure GDA0002761324800000083
where α is an intrinsic constant determined by the properties of the material itself, Ti-X1α of the alloy is 1; r issIs the electron volume effective radius; eFIs a fermi energy.
Fermi energy EFIs the electron volume effective radius rsFunction of (c):
Figure GDA0002761324800000084
Figure GDA0002761324800000085
where M is atomic mass, ρ is density, a0Boltzmann constant, z is the number of valence electrons.
To this end, Ti-X is completed1Lattice distortion energy of the system Δ ELD1Formation enthalpy Δ H1And electron work function phi1And (4) calculating.
III calculation of Ti-XiLattice distortion energy Δ E of the remaining elements in the systemLDiFormation enthalpy Δ HiAnd electron work function phii：
The other elements are metal elements except aluminum in the periodic table of elements.
The calculation of Ti-XiLattice distortion energy Δ E of the remaining elements in the systemLDiFormation enthalpy Δ HiAnd electron work function phiiMeans calculation of Ti-XiIn the system X2～nLattice distortion energy Δ E of the element(s)LDiFormation enthalpy Δ HiAnd electron work function phii。
Repeating said step II to respectively obtain said Ti-XiThe rest elements in the system are added into the pure titanium one by one to form n-1 Ti-X elements in turniSystem, i ═ 2,3, … … n, andeach Ti-X was calculated in turn according to the calculation method described in the above IIiLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phiiUntil said n-1 Ti-X are obtainediLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phii。
Obtaining Ti-X consisting of all metal elements in the periodic table of the elements through the II and the IIIiLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phii。
Ti-X composed of all metal elements in the periodic table obtained by comparisoniLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phiiAnd selecting alloy elements to form a target research system.
The criteria for selecting the alloy elements are as follows:
1. the lattice distortion caused by the addition of the element is small;
2.Ti-Xithe absolute value of the formation enthalpy of the system is large;
3.Ti-Xithe electron work function of the system is large.
The selected alloying elements are shown in table 1.
TABLE 1 Ti-XiLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phii
Figure GDA0002761324800000091
In this embodiment, the objective study system is determined as follows: Ti-Mo-Nb-Cr-Al-Fe.
Step 2, calculating the yield strength sigma of the target research system0.2：
Calculating yield strength sigma of target research system based on alloy strengthening model0.2The alloy strengthening model is disclosed in chemistry Z, Jinshan L, Yi W, et al, reforming the local lattice strains and strain mechanics of Ti alloys [ J]Comparative Materials Science 2018,152: 169-.
The alloy strengthening model is as follows:
σ0.2＝K1Φ6+C...................................................(4)
k in alloy strengthening model1And C is a constant term, where K1＝-1.0653，C＝5076.19251。
The main role of the alloy strengthening model is the electron work function phi of a target research system; the calculation formula of the electron work function phi of the target research system is as follows:
Φ＝∑zkφk...................................................(5)
where Φ is the electron work function of the target research system; z is a radical ofkIs the molar mass of the k element, phikIs the electron work function of the Ti-K system.
Obtaining the yield strength sigma in a target research system through the alloy strengthening model0.2Electronic work function phi and yield strength sigma of alloy larger than 1200MPa0.2As shown in table 2.
TABLE 2 Electron work function Φ and yield Strength σ for alloys with yield Strength greater than 1200MPa0.2
Alloy system Φ/eV σ0.2/MPa
Ti-7Mo-3Al-3Cr-3Nb 3.91326 1225.418
Ti-7Mo-4Al-4Cr-3Nb 3.93039 1284.738
Ti-7Mo-5Al-4Cr-3Nb-0.5Fe 3.93658 1338.119
Ti-6Mo-5Al-3Cr-3Nb-1Fe 3.87141 1489.543
And 3, checking the components based on the Mo equivalent and the d electronic theory design criterion:
mo equivalent determines the amount and stability of metastable beta phase which can be retained during quenching treatment, and a large amount of experimental data show that the Mo equivalent is 9-11 no matter in an annealing state or a solid solution aging state, and the strengthening efficiency is highest. The alloy is designed to satisfy Mo equivalent of 9-11.
The d-electron theory is developed on the basis of molecular orbital calculation and mainly comprises two parameters: bo value and Md value. The value of the parameter Bo represents the overlap of electron clouds between atoms and is a measure of the strength of covalent bonds between atoms, and the higher the value Bo is, the stronger the bonding between atoms is; the parameter Md value represents the d orbital energy of any one of the alloying elements, and represents the electronegativity characteristic of the alloying element in relation to the transfer of electric charges. The Bo value and the Md value are adjusted to control the phase stability and the performance of the alloy. According to
Figure GDA0002761324800000101
Phase stability diagrams enabling determination of metastable beta titanium alloys
Figure GDA0002761324800000102
The value is 2.30 to 2.42,
Figure GDA0002761324800000103
the value is 2.75 to 2.82. The above-mentioned
Figure GDA0002761324800000104
Is the average value of the values of all alloy elements Bo in a target research system; the above-mentioned
Figure GDA0002761324800000105
Is the average value of the Md values of the respective alloying elements in the target research system.
In designing metastable beta titanium alloy, the final of the target research system
Figure GDA0002761324800000106
And
Figure GDA0002761324800000107
the temperature should be controlled within 2.30-2.42 and 2.75-2.82 respectively to ensure that the designed alloy is a metastable beta titanium alloy.
Of target research systems
Figure GDA0002761324800000108
Value sum
Figure GDA0002761324800000109
The calculation of the values is as follows:
Figure GDA00027613248000001010
Figure GDA0002761324800000111
in the formula, akIs the atomic percentage of the k element, (Md)kAnd (Bo)kMd and Bo values of k elements, respectively
Calculating the yield strength sigma in step 20.2Mo equivalent of the alloy more than 1200MPa,
Figure GDA0002761324800000112
Value sum
Figure GDA0002761324800000113
The results are shown in Table 3.
TABLE 3 yield Strength σ0.2Mo equivalent of the alloy more than 1200MPa,
Figure GDA0002761324800000114
Value sum
Figure GDA0002761324800000115
Value of
Figure GDA0002761324800000116
The calculation results show that the yield strength sigma in step 20.2The Mo equivalent of the alloy more than 1200MPa is 9-11,
Figure GDA0002761324800000117
the values are all between 2.30 and 2.42,
Figure GDA0002761324800000118
the values are all between 2.75 and 2.82, and the design requirements are met.
Step 4, smelting the cast ingot, carrying out mechanical treatment, testing the yield strength of the cast ingot, and verifying the accuracy of design:
the preparation method comprises the following steps of proportioning according to specific chemical components of the alloy in the table 2, preparing an ingot with the weight of more than 20 kilograms by using a vacuum consumable melting furnace according to a conventional method, carrying out solid solution aging heat treatment after cogging and forging, testing the yield strength of the alloy, verifying the correctness of a design result, and finishing the design of the metastable beta titanium alloy. The results are shown in Table 4. The error is less than 10% compared to the yield strength calculated based on the strengthening model described above. It can thus be verified that the design method of the present invention is feasible.
TABLE 4 Experimental values for alloy yield strength
Figure GDA0002761324800000119

Claims (2)

1. A method for designing components of a metastable beta titanium alloy is characterized by comprising the following specific steps:
step 1, establishing a Ti-Xi alloy system and calculating the lattice distortion energy delta E thereof by utilizing a first principle calculation methodLDiFormation enthalpy Δ HiAnd electron work function phiiThe influence of the addition of the alloy elements on the alpha phase stability and the electronic structure is contrastively analyzed, the alloy elements are selected, and a target research system is determined;
the specific calculation method is as follows:
i establishment of Ti-XiThe alloy system of (1):
adding any metal element in the periodic table of elements into pure titanium to establish Ti-XiWherein i is 1,2, … … n; using aluminium as alloy element X1Adding to pure titanium to form Ti-X1The method is characterized in that the method comprises the following steps of,
II determining Ti-X1Lattice distortion energy Δ E of the alloy system of (1)LDFormation enthalpy Δ H and electron work function Φ:
calculating the lattice distortion energy Delta ELD1And enthalpy of formation Δ H1The specific calculation process is as follows:
by the equilibrium energy E of the pure titanium obtained0(Ti) and Ti-X1Equilibrium energy E of the system0(Ti-X1) Determining the lattice distortion energy Δ E using equation (1)LD1：
ΔELD1＝E0(Ti-X1)-E0(Ti).....................................(1)
Calculating the Ti-X1Lattice distortion energy of the system Δ ELD1The specific process is as follows:
establishing pure titanium super crystal cell model by using vesta software and adding alloying element X1Ti-X of1A super cell model, which is prepared by VASP software in a computer cluster1The volume of the super-cell model is scaled according to different proportions in sequence to obtain pure titanium super-cell models and Ti-X with different volumes respectively1A super cell model;
the scaling ratios are 0.96, 0.98, 1.00, 1.02 and 1.04, respectively;
for the obtained pure titanium super crystal cell models with different volumes and Ti-X1Performing static calculation on the super cell model; respectively obtaining pure titanium super-cell models and Ti-X with different volumes1The total internal energy Ev and the deformation volume V of the super cell model in a static state; the obtained pure titanium super-cell models with different volumes and Ti-X1The total internal energy Ev and the deformation volume V of the super cell model are respectively brought into a four-parameter Birch-Murnaghan state equation to carry out the fitting of the equilibrium state property, and the equilibrium energy E of the pure titanium is obtained0(Ti) and Ti-X1Equilibrium energy E of the system0(Ti-X1)；
Ti-X obtained by the above1Equilibrium energy E of the system0(Ti-X1) And an alloying element X1Equilibrium energy E of0(X1) Determining the enthalpy of formation Δ H using equation (2)1：
Figure FDA0002761324790000011
Wherein the content of the first and second substances,
Figure FDA0002761324790000012
is Ti-X1Alloy element X in the system1The molar mass of (a);
calculating the Ti-X1Enthalpy of system formation Δ H1The specific process is as follows:
build up alloying element X1The alloying element X is subjected to a VASP software in a computer cluster1The volume of the crystal cell model is scaled according to different proportions in sequence to respectively obtain the alloying element X1Cell models at different volumes; the scaling ratios are 0.96, 0.98, 1.00, 1.02 and 1.04, respectively;
to alloying element X1Carrying out static calculation on the unit cell models in different volumes to respectively obtain alloying elements X1The total internal energy Ev and the deformation volume V of the unit cell model under different volumes in a static state;
the obtained alloying element X1The total internal energy Ev and the deformation volume V of the unit cell model under different volumes are respectively brought into a four-parameter Birch-Murnaghan equation of state for fitting the property of the equilibrium state, and the alloying element X is obtained1Equilibrium energy E of0(X1)；
Calculating Ti-X by using first-nature principle calculation method1Electron work function of the system phi1；
Ti-X1Electron work function of the system phi1The calculation formula of (2) is as follows:
Figure FDA0002761324790000021
where α is an intrinsic constant determined by the properties of the material itself, Ti-X1α of the alloy is 1; r issIs the electron volume effective radius; eFIs a fermi energy;
thus, Ti-X was determined1Lattice distortion energy of the system Δ ELD1Formation enthalpy Δ H1And electron work function phi1；
III calculation of Ti-XiLattice distortion energy Δ E of the remaining elements in the systemLDiFormation enthalpy Δ HiAnd electron work function phii：
The Ti-XiThe rest elements in the system are metal elements except aluminum in the periodic table of elements;
repeating said step II to respectively obtain said Ti-XiThe rest elements in the system are added into the pure titanium one by one to form n-1 Ti-X elements in turniSystem i 2,3, … … n and calculating each Ti-X in turn according to the calculation method described in said iiiLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phiiUntil said n-1 Ti-X are obtainediLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phii；
Obtaining Ti-X consisting of all metal elements in the periodic table of the elements through the II and the IIIiLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phii；
Ti-X composed of all metal elements in the periodic table obtained by comparisoniLattice distortion energy of the system Δ ELDiFormation enthalpy Δ HiAnd electron work function phiiSelecting alloy elements to form a target research system;
the criteria for selecting alloying elements are as follows:
i, the lattice distortion caused by the addition of the element is smaller;
ⅱ Ti-Xithe absolute value of the formation enthalpy of the system is large;
ⅲ Ti-Xithe electron work function of the system is large;
step 2, calculating the yield strength sigma of the target research system0.2：
Calculating yield strength sigma of target research system based on alloy strengthening model0.2；
The alloy strengthening model is as follows:
σ0.2＝K1Φ6+C...................................................(4)
k in alloy strengthening model1And C is a constant term, where K1＝-1.0653，C＝5076.19251；
The main role of the alloy strengthening model is the electron work function phi of a target research system; the calculation formula of the electron work function phi of the target research system is as follows:
Φ＝∑zkφk...................................................(5)
where Φ is the electron work function of the target research system; z is a radical ofkIs the molar mass of the k element, phikIs the electron work function of the Ti-K system;
obtaining the yield strength sigma in a target research system through the alloy strengthening model0.2Electronic work function phi and yield strength sigma of alloy larger than 1200MPa0.2；
And 3, checking the components based on the Mo equivalent and the d electronic theory design criterion:
the designed alloy meets the requirement that the Mo equivalent is 9-11, and the Mo equivalent is determined by a Mo equivalent calculation formula;
designed metastable beta titanium alloy
Figure FDA0002761324790000031
And
Figure FDA0002761324790000032
the temperature should be controlled within 2.30-2.42 and 2.75-2.82 respectively; of target research systems
Figure FDA0002761324790000033
Value sum
Figure FDA0002761324790000034
The calculation of the values is as follows:
Figure FDA0002761324790000035
Figure FDA0002761324790000036
in the formula: a iskIs the atomic percentage of the k element, (Md)kAnd (Bo)kMd and Bo values for the k element, respectively; the Md value is the d orbital energy of any alloy element, is related to charge transfer, and shows the electronegativity characteristic of the alloy element;
Figure FDA0002761324790000037
is the average value of the Md values of all the alloy elements in a target research system; the Bo value is the overlap of electron clouds between atoms and is a measure of the strength of covalent bonds between atoms;
Figure FDA0002761324790000038
is the average value of the values of all alloy elements Bo in a target research system;
step 4, smelting the cast ingot, carrying out mechanical treatment, testing the yield strength of the cast ingot, and verifying the accuracy of design:
the method comprises the steps of proportioning according to specific chemical components of the alloy meeting yield strength requirements, preparing an ingot with the weight of more than 20 kilograms by using a vacuum consumable melting furnace according to a conventional method, carrying out solid solution aging heat treatment after cogging and forging, testing the yield strength of the alloy, verifying the correctness of a design result, and finishing the design of the metastable beta titanium alloy.
2. The method for designing the composition of the metastable beta-titanium alloy according to claim 1, wherein the Mo equivalent of the alloy with the yield strength of more than 1200MPa in the step 3 is 9-11,
Figure FDA0002761324790000039
the values are all 2.30-2.42,
Figure FDA00027613247900000310
the values are all 2.75-2.82.
CN201910643057.6A 2019-07-17 2019-07-17 Component design method of metastable beta titanium alloy Active CN110387485B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910643057.6A CN110387485B (en) 2019-07-17 2019-07-17 Component design method of metastable beta titanium alloy

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910643057.6A CN110387485B (en) 2019-07-17 2019-07-17 Component design method of metastable beta titanium alloy

Publications (2)

Publication Number Publication Date
CN110387485A CN110387485A (en) 2019-10-29
CN110387485B true CN110387485B (en) 2021-02-02

Family

ID=68285047

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910643057.6A Active CN110387485B (en) 2019-07-17 2019-07-17 Component design method of metastable beta titanium alloy

Country Status (1)

Country Link
CN (1) CN110387485B (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111326220B (en) * 2020-04-16 2023-08-15 重庆大学 Design method of high-strength and high-toughness zirconium-titanium-based alloy
CN112349352B (en) * 2020-11-06 2022-05-27 福州大学 High-entropy alloy lattice distortion quantity calculation method based on atom occupying ordering behavior
CN112542217B (en) * 2020-11-11 2022-08-09 南京理工大学 Design method of high-strength high-toughness high-entropy alloy
CN112528465B (en) * 2020-11-14 2023-06-13 辽宁石油化工大学 Near alpha titanium alloy performance optimization and component reverse design method based on Lesion theory
CN112992287B (en) * 2021-02-18 2022-06-28 山东省科学院新材料研究所 Prediction method for solid solubility regulation effect of additive element on target element and application thereof
CN113053464A (en) * 2021-03-18 2021-06-29 西南交通大学 Novel titanium alloy and component design method thereof

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101763450B (en) * 2009-12-31 2012-04-04 辽宁工业大学 Titanium alloy component quantifying design method
JP6851147B2 (en) * 2016-06-10 2021-03-31 株式会社神戸製鋼所 Titanium alloy forged material
CN107460370A (en) * 2017-08-17 2017-12-12 中南大学 A kind of low-cost high-strength high-ductility metastable β Titanium-alloy and preparation method thereof
CN107665274B (en) * 2017-09-08 2021-05-18 东南大学 Method for designing low-elasticity-modulus titanium alloy
CN108446478B (en) * 2018-03-14 2021-07-06 中南大学 Design method of multi-component high-strength titanium alloy
CN110010210B (en) * 2019-03-29 2021-03-19 北京科技大学 Multi-component alloy component design method based on machine learning and oriented to performance requirements

Also Published As

Publication number Publication date
CN110387485A (en) 2019-10-29

Similar Documents

Publication Publication Date Title
CN110387485B (en) Component design method of metastable beta titanium alloy
Xiao et al. Constitutive modeling of flow behavior and microstructure evolution of AA7075 in hot tensile deformation
Dehghani et al. Optimizing the bake hardening behavior of Al7075 using response surface methodology
CN103834837B (en) Al-Zn-Cu-Mg acieral and manufacture method thereof and purposes
Soto et al. Thermodynamic analysis of high entropy alloys and their mechanical behavior in high and low-temperature conditions with a microstructural approach-A review
Ma et al. Influence of solution heat treatment on mechanical response and fracture behaviour of aluminium alloy sheets: An experimental study
EP2966185B1 (en) Titanium alloy for fastener applications
Zhang et al. Progress in characterization methods for thermoplastic deforming constitutive models of Al–Li alloys: a review
Maboud et al. Process parameters optimization of friction stir processed Al 1050 aluminum alloy by response surface methodology (RSM)
Sonkusare et al. Establishing processing-microstructure-property paradigm in complex concentrated equiatomic CoCuFeMnNi alloy
Li et al. Research progress on hot deformation behavior of high-strength β titanium alloy: Flow behavior and constitutive model
Chao et al. A modified Johnson-Cook model with damage degradation for B4Cp/Al composites
Zhang et al. Effect of deformation degree on the creep age forming of 7475 aluminum alloy: The feasibility of the extended deformation range
Ji et al. The effects and utility of homogenization and thermodynamic modeling on microstructure and mechanical properties of SS316/IN718 functionally graded materials fabricated by laser-based directed energy deposition
Tian et al. Research on the mechanical properties and hot deformation behaviors of spray-deposited 7034 Al alloy processed by forward extrusion
Muñoz-Ibáñez et al. Design and application of a quantitative forecast model for determination of the properties of aluminum alloys used in die casting
Li et al. Microstructural and constitutive relationship in process modeling of hot working: The case of a 60Mg-30Pb-9.2 Al-0.8 B magnesium alloy
Alaneme et al. Softening resistance, dimensional stability and corrosion behaviour of alumina and rice husk ash reinforced aluminium matrix composites subjected to thermal cycling
CN112733330B (en) Method for predicting thermal deformation behavior and yield strength after forming of aluminum alloy
Wang et al. Revealing hot deformation behavior and optimizing process parameters of as-cast Ti–5Al–5Mo–5V–1Cr–1Fe alloy
Yang et al. Microstructure evolution, deformation behavior and processing performance of TNM TiAl alloy
Li et al. Simulation of a wrought Al-Cu-Mg-Ag alloy during hot deformation based on constitutive modelling and process maps
Singh et al. Optimization and prediction of cutting parameters in the end milling process for cast aluminium B4C based composite
CN112528465A (en) Near alpha titanium alloy performance optimization and component reverse design method based on Leeb's theory
Wang et al. A novel laser cladding AlMgZnCuErZr alloy: Material genetic design, strengthening andtoughening mechanisms

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant